International Polar Year 2007–2008 - WMO

addressed these goals.
High resolution imagery is a commonly used data set
to visualize a region and, in Antarctica, often replaces
maps. Surprisingly, before IPY, the highest resolution
data set of Antarctica used radar, not visible, imagery.
As IPY approached, a joint U.S.-U.K. effort to produce
the Landsat Image Mosaic of Antarctica (LIMA, http://
lima.usgs.gov) began. During IPY, LIMA was released,
capturing the status of the of the Antarctic Ice Sheet
surface for the period 1999-2003. Extensive image
processing was completed to rigorous scientific
conditions to produce a scientifically valuable mosaic
data set of surface reflectances. The outcome of this
IPY project gives the public and educators a new,
exciting and flexible tool to increase their familiarity
with Antarctica (http://lima.nasa.gov). LIMA has been
used extensively in the classroom and by media to
add a real-look dimension to Antarctic activities. LIMA
also serves the science research community with a
new research tool of meaningful surface reflectances
to facilitate not just field planning and exploration of
the Antarctic surface, but also quantitative analyses
that utilize surface reflectance data. LIMA offers
parallel views of the surface with synthetic aperture
radar from the co-registered Radarsat data set. The
LIMA interface allows interested users to download
either the mosaiced data or the individual scenes.
Two biologists used the LIMA mosaic to map penguin
rookeries over all of Antarctica, finding a number of
previously unknown rookeries and identifying some
abandoned rookeries based on the spectral (true
color) signature of rookeries (Fretwell, 2009).
Following from the LIMA and during the LIMA
period of 1999-2003 was the project ASAID defining
the precise position of the Antarctic grounding
line by including ICESat and SAR data at 15 meters
resolution and, from it, the total ice discharge from the
Antarctic continent. Scientists from Norway, the U.K.,
New Zealand, Italy, Germany, Australia and the U.S.
produced a comprehensive estimate of the surface
accumulation and ice discharge for the Antarctic
cryosphere. Additional products were the first-ever
mapping of the “hydrostatic line” where floating
ice is in hydrostatic equilibrium, the first complete
mapping of surface velocity across the grounding line.
Previous estimates of the Antarctic discharge flux had
been limited to the fast moving outlet glaciers. Some
field data collected during IPY by the British Antarctic
Survey was used for validation. Each of these new data
products are benchmark data sets that will be used to
measure change of the cryosphere in the future. New
techniques were employed to derive surface elevations
from Landsat imagery using ICESat altimetry as
control while customized software was developed to
provide analysts with tools for combining these data
and drawing and editing the grounding line.
Russian research during IPY included Antarctic
Ice Sheet and sea water interaction, geophysical
investigations of ice stream-lines and subglacial lakes,
and surface ice accumulation and discharge. During
IGY, surface traverses across the Antarctic Ice Sheet
were used to generate the first accurate estimates of
the volume of ice stored on the continent.
During IPY 2007–2008, surface traverses were
used to make key in situ measurements of the ice
sheet in locations many of which had not been
visited for decades. During the planning phases of
IPY, one of the first concepts offered (by Heinz Miller
of AWI under the title IDEA) was traverses along the
divides of the ice sheets collecting shallow ice cores
to capture the accumulation record and to provide
the logistical infrastructure for other detailed work
such as aerogeophysics. Much of this concept was
implemented, although not always under the umbrella
of IDEA. The long running ITASE program targeted
where and how Antarctic physical and chemical
climate has or has not changed over the last several
hundred years with a view toward assessing future
climate change over Antarctica. ITASE continued into
IPY with traverses extended from McMurdo to the
South Pole and from Dronning Maud Land to Dome
F and on to the Japanese Base Syowa. Traverses were
also completed by a joint Norwegian-U.S. team that
covered one of the major ice divides and surveyed
major sub-glacial lakes, as well as one component of
the PANDA program that traveled from the coast to
Dome A.
Making use of mobile platforms in the interior of
Antarctica, the Japanese-Swedish Antarctic Expedition,
JASE (November 2007 – February 2008), made
continuous surveys of different parameters, including
sampling and snow and ice radar surveys. The JASE traverse
began in Dronning Maud Land, East Antarctica
at the Swedish base Wasa and reached the Japanese
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